Locking member for sprinkler heads



June 14, 1932. Q P HOWARD 1,863,246

LOCKING MEMBER FOR SPRINKLER HEADS Filed Nov. 2, 1931 .5.- MM M Patented June 14, 1932 UNITED STATES PATENT OFFICE CLIFTON IE. HOWARD, OF WORCESTER, MASSACHUSETTS, ASSIGNOR T ROCKWOOD SPRINKLER COMPANY OF MASSACHUSETTS, OF WORCES'IER, MASSACHUSETTS, A

CORPORATION OF MASSACHUSETTS LOCKING MEMBER FOR SPRINKLER HEADS Application filed November 2, 1931.

This invention relates to sprinkler heads used for fire protective purposes. In the use of such devices rapidity of response to a rise in temperature is of the greatest importance.

It is the principal object of my invention to provide an improved construction in a locking member or strut for a sprinkler head, so designed that it will respond very quick ly to temperature changes.

A further object of the invention is to provide a form of locking element which may be easily and economically manufactured and which will be fully reliable in use.

My invention further relates to arrangements and combinations of parts which will be hereinafter described and more particularly pointed out in the appended claims.

A preferred form of the invention, together with a slight modification, is shown in the drawing, in which Fig. 1 is a side elevation of a sprinkler head having my improvements embodied therein;

Fig. 2 is a bottom View of the member or strut, looking in the direction of the arrow 2 in Fig. 1;

Fig. 3 is a sectional side elevation, taken along the line 3-3 in Fig. 2

Figs. 4 and 5 are a plan and side elevation of a blank from which my improved locking element is formed;

Fig. 6 is aside elevation of the blank after the first forming operation;

Fig. 7 is an end view thereof, looking in the direction of the arrow 7 in Fig. 6;

Fig. 8 is a sectional side elevation, taken along the line 88 in Fig. 7;

Fig. 9 is a transverse sectional view, taken along the line 9-9 in Fig. 8;

Fig. 10 is a side elevation of the blank after a second forming operation;

Fig. 11 is a bottom view thereof, looking in the direction of the arrow 11 in Fig. 10;

Fig. 12 is a sectional side elevation, taken along the line 1212 in Fig. 11;

Fig. 13 is a transverse section, taken along the line 1313 in Fig. 11;

Fig. 14 is a side elevation of the finished Serial No. 572,613.

locking element after a third forming operation;

Fig. 15 is a sectional side elevation of the finished locking element;

Fig. 16 is a side elevation of a modified construction Fig. 1'7 is a transverse section, taken along the line 17-17 in Fig. 16, and

Fig. 18 is a transverse section of a further modification.

Referring to Fig. 1, I have shown a sprinkler head which is in general of a usual commercial type known as a Fig. A sprinkler head and comprising a base 10 having a water passage therethrough, normally closed by a cap 11. A post 12 is seated on the cap 11 and the upper end of the post engages one end of a lever 13. A locking member or strut M is interposed between the lower end of the base 12 and the outer end of the lever 13. The parts are held in assembled relation by a screw 14, threaded into the top portion of an open frame member 15 supported on the base 10 and carrying a spreader plate 16.

The locking member or strut M is formed of two cooperating locking elements 20 and 21, normally secured together by'the application of solder S or of some other low-melting alloy.

The right hand end of the locking element 20, as viewed in Fig. 3, engages a shoulder 22 on the element 21, so that the two parts 20 and 21 collectively form a thrust member interposed between the lower end of the post 13 and the outer end of the member 13 and under compression when assembled in operative position.

\Vhen a rise in temperature causes the sol der S to melt, the elements 20 and 21 separate by swinging about the shoulder 22, as indicated in dotted lines in Fig. 3, and the sprinkler head is thus released.

The details of construction of the locking element 20 are fully shown and described in the copending application of Robert H. Russell, Serial No. 499,520, filed Dec. 2, 1930, and the present application relates to the specific construction of the locking element 21. This element has previously been made as a solid casting or stamping of substantial un-"mm cross section, as shown in said prior application.

I have discovered that the relatively large amount of metal in the locking element previously used retards the release of the sprinkler on a rise in temperature. According ly I have devised a much lighter construction by which this locking element can be made inimproved form but without substantial reduction in strength. This improved construction is shown in the drawing and will now be described.

I preferably produce my improved locking element 21 from thin sheet metal, such as sheet copper or bronze. I first obtain a blank B of the out-line shown in Figs. 4 and 5. I then submit the blank to a press operation by which the sides of the blank are turned downward, as indicated at 30 in Figs. 6 and 9. One end of the blank is displaced upwardly,

3 as indicated at 31, with the eXtremeend portion turned downward, as indicated at I then subject the partially formedlocking element to a second press operation by which it is transformed to the construction shown in Figs. 10 to 13. This second operation produces sharp interior angles and fiat side walls and also shapes the end portion 32 so that it is well adapted to engage a shoulder or abutment on the'end of the lever 13 The locking element 21 is then subjected to a third press operation by which the shoulder 22is given an abruptangularly disposed surface, well adapted to resist the end thrustof the associated locking element 20.

The locking element 21 is now complete andready' forassembly with the element 20, as indicated in -Figs.i2 -and'3. The flat portions of the elements 20 and 21 are first sweated together with solder, and a substantial amount of solder is applied around the edges and across the end of the element 21. Y 'A locking element thus constructed maybe easily and cheaply manufactured and the assembled locking member or strut is found to respond much more quickly to changes in temperature than with the previous construction in which one orboth locking elements were formed'from relatively heavy metal.

In Figs, 16 and 17 I have shown a construc- 'tion in whichthe locking element 40 is reenfo'rced' by forming inner flange ll in such a position as to resist buckling of the -ele-' ment lOunder pressure applied to the end portion 42.

In Fig. '18 I have indicated that the strength of the device may be still further increased by corrugating the flat or body portion of the locking element. 7

All three forms of the invention are satisfactory in use and, as previously stated, substantially decrease thetime element in the release, of a sprinkler head.

Having. thus described my invention and V the-advantages thereof, I do not wish to be limited to the details herein disclosed, other- Wise than as set forth in the claims, but what I claim is 1. In a sprinkler head, a locking element formed of thin metal of substantially uniform thickness throughout and havinfig an extendedbody portion, an upwardly 0 set end portion and depending side flanges extending the full length of the body and end portions andsubstantially stiffening said locking element. 7

2. The combination in a locking element as set forth in claim 1, in which widened portions of said side flanges are folded inward to provide increased strength at the point at which the body portion and the upturned end portion meet. 7

" 3. The combination in a locking element as set forth in claim 1, in which the body portion is provided with corrugations eX- tending lengthwise thereof and providing additional stiffness therefor.

1-. The combination in a locking element as set forth in claim 1, in which the side flanges increase progressively in width t0- ward the up-turned end portion of said locking element.

5. In a sprinkler head, a locking element formed of thin metal of substantially uniform thickness throughout andhaving an extended body portion, an upwardly offset end portion having its outer edge portion projected downward to provide an end shoulder, and depending side flanges extending the full length of said body and end portions.

In testimony whereof I have hereunto aflixed my signature.

' CLIFTON P. HOWARD. 

